Regina McDonald arrived early at Pittsburgh Police Bureau headquarters for her first day as the acting chief. Mayor Luke Ravenstahl -- who asked for Chief Nate Harper's resignation -- came by for an afternoon meeting.

Former Washington County District Attorney Steven Toprani was tapped by Mayor Luke Ravenstahl, in part because of his record prosecuting corrupt police officers.

“I investigated and prosecuted a number of instances of what we'd call police misconduct ranging from stealing from evidence lockers to overt corrupt activities,” Toprani said.

Two years ago, former Monongahela police officer George Langan was convicted of charges he tipped off drug dealers. He was one of several police officers convicted of corruption charges after Toprani convened Washington County's first grand jury in three decades.

Now, Toprani is turning his attention to allegations that Pittsburgh police from Harper on down abused the rules for outside employment. The FBI has taken boxes of records from police headquarters.

Among the recent revelations: Harper promoted Eric Holmes to commander, while at the same time the two men were business partners.

Also, Harper was a business partner with Officer Tonya Ford and she had another side business selling police memorabilia.

Toprani said officers working side jobs can create conflicts of interest.

The Obama administration will unveil a major climate change plan Monday aimed at a large reduction in greenhouse gas emissions from the nation's coal-burning power plants, a senior administration official told CNN.